(CNN) -- Unheralded Frenchman Vincent Jay caused a massive upset by claiming the first gold medal of Sunday's competition at the Vancouver Winter Games by winning the men's sprint biathlon at Whistler Olympic Park.

A second gold for France soon followed in the men's nordic combined event as Jason Lamy Chappuis prevailed in a thrilling cross country section.

He overtook American Johnny Spillane on the final corner to triumph with Italian Alessandro Pittin in the bronze medal position.

Chappuis, the pre-event favorite, had been fifth behind leader Janne Ryynaenen of Finland after the opening ski-jumping discipline, but quickly made up lost ground.

But he admitted later that he had left his victory charge mighty late.

"On the last hill, Johnny (Spillane) was far ahead of me and I honestly didn't think I could get the gold medal. I thought it was done," he said.

In the first medal event of the day his compatriot Jay took advantage of an early start position in his event which combines cross country skiing and shooting to win in 24 minutes 7.9 seconds.

Norwegian Emil Hegle Svendsen claimed the silver medal but was 12.2 seconds adrift of Jay, who was making his Olympic debut.

Croatian Jakov Fak, who took bronze, was a further 1.8 seconds adrift.

Heavy snow showers made conditions more difficult for the favored later starters and Norwegian legend Ole Einar Bjoerndalen failed in his bid for a 10th Olympic medal.

Bjoerndalen, who has won five golds, suffered four penalties in the shooting sections and could only finish 17th, nearly two minutes behind Jay.

The 36-year-old Bjoerndalen's next chance will come in Tuesday's 12.5km pursuit.

The lowly-ranked Jay could hardly believe he had triumphed.

"I still do not realize that I have won. Weather conditions were good for me, but not for the [World Cup] leaders. My ski technicians did a great job today," he told reporters.